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The increasing production of zinc oxide nanoparticles and their use in products of sanitary interest make the analysis and characterization extremely important from the point of view of public health and environmental risk. This work aimed to validate the methodology using SP-ICP-MS to measure and quantify nanoparticles of ZnONPs and dissolved zinc—Zn(i). This study pointed out that the method was suitable for the purpose, presenting satisfactory results for the recovery and precision test for Zn(i) and size of NPs. The limits of detection size, dissolved zinc concentration, and particle concentration were 67 nm, 0.4 µg L−1, and 1.08 × 105 particles mL−1, respectively. Thus, the results obtained demonstrate that the technique can be used to determine the size and concentration of Zn(i) in different products. [ABSTRACT FROM AUTHOR]

The use of a new nanomaterial in the feed chain requires a risk assessment that involves in vitro gastrointestinal digestions to predict its degradation and oral exposure to nanoparticles. In this study, a nanosilver-based material was incorporated into pig and chicken feed as a growth-promoting additive and subjected to the corresponding in vitro gastrointestinal digestions. An inductively coupled plasma mass spectroscopy (ICP-MS) analytical platform was used to obtain information about the silver released in the different digestion phases. It included conventional ICP-MS for total silver determination, but also single particle ICP-MS and coupling to hydrodynamic chromatography for detection of dissolved and particulate silver. The bioaccessible fraction in the intestinal phase accounted for 8–13% of the total silver, mainly in the form of dissolved Ag(I) species, with less than 0.1% as silver-containing particles. Despite the additive behaving differently in pig and chicken digestions, the feed matrix played a relevant role in the fate of the silver. [ABSTRACT FROM AUTHOR]

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Environmental context: Plastic pollution is widespread and continues to be a major concern, both for the environment and human health. Identifying nanoplastics is challenging but is important to understand how they behave once in the environment. It is shown that a combination of single particle (SP) and single cell (SC) inductively coupled plasma mass spectrometry (ICP-MS) can be used to quantify nanoplastics on a per cell basis after exposure to algal cells. The effects of plastic pollution on human health and the environment are not well known but there are significant concerns. Although research has increased in recent years, there remain many obstacles to the quantification of nanoplastics. This rapid communication demonstrates that combined single particle (SP)– and single cell (SC)–inductively coupled plasma–mass spectrometry (ICP-MS) provide a novel means to quantify pre-formed core–shell metal–plastic composite nanoparticles when exposed to two freshwater algal cells, Cryptomonas ovata (C. ovata) and Cryptomonas ozolini (C. ozolini). It is shown that individual palladium plastic nanoparticles (Pd NPPs) exposed to algal cells form agglomerates in the cell suspension respectively consisting of 165 and 157 (±3.8) individual Pd NPPs for C. ozolini and C. ovata cells, and that the agglomerates are also cell-associated with 1.75–1.85 agglomerates per cell. Environmental context. Plastic pollution is widespread and continues to be a major concern, both for the environment and human health. Identifying nanoplastics is challenging but it is important to understand how they behave once in the environment. It is shown that a combination of single particle (SP)– and single cell (SC)–inductively coupled plasma–mass spectrometry (ICP-MS) can be used to quantify nanoplastics on a per cell basis after exposure to algal cells. (Image credit: E. C. Bair.) [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs), widely used in various fields of technology as an antimicrobial agent, represent a new type of environmental pollutant. Through various routes, AgNPs might penetrate into agricultural crops and foodstuffs. It is important to know if AgNPs contained in food persist in digested food and are therefore available for entering the inner organs of the consumer's body. Using the technique of single-particle ICP-MS, we analysed the changes in the number and size distribution of AgNPs added to a sample of bread submitted to in vitro simulated gastrointestinal digestion. The majority of silver, in terms of mass, was transformed from the state of particles to the dissolved state during bread digestion, but the number of particles was reduced by 25% only. The most abundant particle size was reduced from 60 nm to 49 nm. Hence, a substantial part of transformed nanoparticles is still present in food digestate. This means that AgNPs consumed together with food can theoretically enter the inner cells of human body. [ABSTRACT FROM AUTHOR]

AbstractSelenium is a non-essential element with beneficial and toxic effects on plants, whose exact role in plant physiology leaves many unanswered questions. Various species of hydroponically grown plants produce defined selenium nano particles (SeNP) with a narrow size distribution and about 2 million selenium atoms by biosynthesis when being exposed to selenite, proving that green synthesis of SeNP is not only possible in plants extracts, but also in living organisms. The detection was performed with single particle inductively coupled plasma mass spectrometry. These results require a new view of the selenium biochemistry in plants and its impact on nutrition, food sciences and medicine. To the best of our knowledge, this is the first report on the synthesis of elemental nanoparticles in general and selenium nanoparticles in particular by living plants.

Selenium is a non-essential element with beneficial and toxic effects on plants, whose exact role in plant physiology leaves many unanswered questions. Various species of hydroponically grown plants produce defined selenium nano particles (SeNP) with a narrow size distribution and about 2 million selenium atoms by biosynthesis when being exposed to selenite, proving that green synthesis of SeNP is not only possible in plants extracts, but also in living organisms. The detection was performed with single particle inductively coupled plasma mass spectrometry. These results require a new view of the selenium biochemistry in plants and its impact on nutrition, food sciences and medicine. To the best of our knowledge, this is the first report on the synthesis of elemental nanoparticles in general and selenium nanoparticles in particular by living plants. [ABSTRACT FROM AUTHOR]

Selenium is an essential trace element in human nutrition. Recent findings suggest that the biosynthesis of selenium nano particles (SeNPs) in plants might be a ubiquitous phenomenon. We investigated the potential of SeNP biosynthesis in food plants and our core objective was to explore the commonness and possible ubiquitousness of nano selenium in food plants and consequently in the human diet. By growing a variety of plants in controlled conditions and the presence of selenite we found strong evidence that SeNPs are widely present in vegetables. The shoots and roots of seven different plants, and additionally Brazil nuts, were analyzed with single-particle inductively coupled plasma mass spectrometry with a focus on edible plants including herbs and salads. SeNPs were found in every plant of our study, hence we conclude, that SeNPs are common ingredients in plant-based food and are therefore eaten daily by most humans. Considering the concerning worldwide prevalence of selenium deficiency and the great physiological properties of SeNPs, we see a high potential in utilizing this discovery. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs), widely used in various fields of technology as an antimicrobial agent, represent a new type of environmental pollutant. Through various routes, AgNPs might penetrate into agricultural crops and foodstuffs. It is important to know if AgNPs contained in food persist in digested food and are therefore available for entering the inner organs of the consumer’s body. Using the technique of single-particle ICP-MS, we analysed the changes in the number and size distribution of AgNPs added to a sample of bread submitted to in vitro simulated gastrointestinal digestion. The majority of silver, in terms of mass, was transformed from the state of particles to the dissolved state during bread digestion, but the number of particles was reduced by 25% only. The most abundant particle size was reduced from 60 nm to 49 nm. Hence, a substantial part of transformed nanoparticles is still present in food digestate. This means that AgNPs consumed together with food can theoretically enter the inner cells of human body.

The use of nanoparticles in agrichemical formula and food products as additives has increased their chances of accumulation in humans via oral intake. Due to their potential toxicity, it is critical to understand their fate and distribution following oral intake. Cerium oxide nanoparticle (CeO2NP) is commonly used in agriculture and is highly stable in the environment. As such, it has been used as a model chemical to investigate nanoparticle's distribution and clearance. Based on their estimated human exposure levels, 0.15–0.75 ​mg/kg body weight/day of CeO2NPs with different sizes and surface charges (30–50 ​nm with negative charge and 25 ​nm are unlikely to accumulate in mouse organ after oral intake, indicating limited impacts on human health.

Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) is a technique widely used to obtain direct information about the number concentration and the size distribution of nanoparticles in liquid suspensions. However, its methods still lack clear quality control strategies to confirm the validity of the information derived from them. Only the detection of the complete size distribution of the nanoparticles in a sample over the size critical value ensures obtaining unbiased quantitative information, otherwise information should be restricted to report the presence of nanoparticles over a certain size and number concentration since their actual total number concentration is underestimated and the size overestimated. Under the latter conditions, data processing produces histograms showing the tails of the incomplete size distributions, although apparently, complete distributions can also be obtained when particle events are recorded as peaks, as reported here for the first time. The occurrence of these misleading situations must be critically evaluated for each SP-ICP-MS analysis. An approach, based on estimation of size critical values and successive dilutions, is proposed for the assessment of the validity of the quantitative information obtained, together with specific criteria for reconsidering the information that can be derived from those measurements. The approach was verified with different case studies and applied to the analysis of complex nanomaterials, confirming the validity of the reported information by comparison with other techniques. A calculation tool is also included to facilitate the estimation of size critical values under experimental conditions. [ABSTRACT FROM AUTHOR]

The work described herein assesses the ability to characterize gold nanoparticles (Au NPs) of 50 and 100 nm, as well as 60 nm silver shelled gold core nanospheres (Au/Ag NPs), for their mass, respective size, and isotopic composition in an automated and unattended fashion. Here, an innovative autosampler was employed to mix and transport the blanks, standards, and samples into a high-efficiency single particle (SP) introduction system for subsequent analysis by inductively coupled plasma–time of flight–mass spectrometry (ICP-TOF-MS). Optimized NP transport efficiency into the ICP-TOF-MS was determined to be >80%. This combination, SP-ICP-TOF-MS, allowed for high-throughput sample analysis. Specifically, 50 total samples (including blanks/standards) were analyzed over 8 h, to provide an accurate characterization of the NPs. This methodology was implemented over the course of 5 days to assess its long-term reproducibility. Impressively, the in-run and day-to-day variation of sample transport is assessed to be 3.54 and 9.52% relative standard deviation (%RSD), respectively. The determination of Au NP size and concentration was of <5% relative difference from the certified values over these time periods. Isotopic characterization of the 107Ag/109Ag particles (n = 132,630) over the course of the measurements was determined to be 1.0788 ± 0.0030 with high accuracy (0.23% relative difference) when compared to the multi-collector–ICP-MS determination. [ABSTRACT FROM AUTHOR]

The increasing use of nanopesticides has raised concerns about their effects on crop plants and the impact of human health as well as ecological effects. While increased uptake of metal ions has been observed before, to date, very few studies have demonstrated the presence of nanoparticles in edible tissues. Single-particle inductively coupled plasma–mass spectrometry (sp-ICP-MS) has been suggested as a powerful tool to detect inorganic nanoparticles (NPs) in environmental samples. Here, we exposed edible plant tissues from lettuce, kale, and collard green to nano-CuO, simulating its use as a nanopesticide. We applied sp-ICP-MS to demonstrate the presence of nanoparticles, both in the water used to rinse crop leaf surfaces exposed to nano-CuO and within the leaf tissues. Lettuces retained the highest amounts of nCuO NPs on the leaf surface, followed by collard green and then kale. Surface hydrophilicity and roughness of the leaf surfaces played an important role in retaining nano-CuO. The results indicate that most of the nanoparticles are removed via washing, but that a certain fraction is taken up by the leaves and can result in human exposure, albeit at low levels.

Selenium is an essential trace element in human nutrition. Recent findings suggest that the biosynthesis of selenium nano particles (SeNPs) in plants might be a ubiquitous phenomenon. We investigated the potential of SeNP biosynthesis in food plants and our core objective was to explore the commonness and possible ubiquitousness of nano selenium in food plants and consequently in the human diet. By growing a variety of plants in controlled conditions and the presence of selenite we found strong evidence that SeNPs are widely present in vegetables. The shoots and roots of seven different plants, and additionally Brazil nuts, were analyzed with single-particle inductively coupled plasma mass spectrometry with a focus on edible plants including herbs and salads. SeNPs were found in every plant of our study, hence we conclude, that SeNPs are common ingredients in plant-based food and are therefore eaten daily by most humans. Considering the concerning worldwide prevalence of selenium deficiency and the great physiological properties of SeNPs, we see a high potential in utilizing this discovery.

Selenium nanoparticles (SeNPs) have recently attracted attention because they combine the benefits of Se and lower toxicity compared to other chemical forms of this element. In this study, SeNPs were synthesized by a green method using ascorbic acid as the reducing agent and polyvinyl alcohol as stabilizer. The nanoparticles were widely characterized. To determine the total concentration of Se by ICP-MS, several isotopes and the use of He as collision gas were evaluated, which was effective in minimizing interferences. A method for sizing SeNPs by single particle ICP-MS (SP-ICP-MS) was developed. For this purpose, He and H2 were evaluated as collision/reaction gases, and the second one showed promising results, providing an average diameter of 48 nm for the SeNPs. These results agree with those obtained by TEM (50.1 nm). Therefore, the SP-ICP-MS can be implemented for characterizing SeNPs in terms of size and size distribution, being an important analytical tool for Se and other widely studied nanoparticles (e.g. Ag, Au, Ce, Cu, Fe, Zn). Finally, the antibacterial activity of SeNPs was assessed. The SeNPs showed bacteriostatic activity against three strains of Gram-positive bacteria and were particularly efficient in inhibiting the growth E. faecalis even at very low concentrations (MIC < 1.4 mg lâˆ'1). In addition, a bactericidal activity of SeNPs against S. aureus was observed. These nanoparticles may have potential application in pharmaceutical industry, biomedicine and agriculture. [ABSTRACT FROM AUTHOR]

The engineered silver nanoparticles (AgNPs) have been widely used in various food contact materials (FCMs) based on their antibacterial properties. This widespread use of nanosilver has, however, increased the risk of exposure of AgNPs to human due to their migration from FCMs causing a potential hazard present in foods. Therefore, it is important to establish a reliable and practical method for the detection of AgNPs in food matrices to support risk assessment on AgNPs exposure. Taking the examples of milk and AgNPs-containing breast milk storage bags, this study established an approach for size characterization and quantification of AgNPs in milk and evaluated the relevant silver migration, based on enzymatic digestion and the analysis by asymmetric flow field–flow fractionation (AF4) hyphenated with inductively coupled plasma mass spectrometry (ICP-MS) and single particle inductively coupled plasma mass spectrometry (SP-ICP-MS). No migration of AgNPs was found from breast milk storage bags under various simulated storage conditions as well as extreme scenarios. The suitability and reliability of this method were also validated by the determination of multiple parameters, including accuracy, repeatability, limit of detection (LOD), limit of quantification (LOQ), and recovery, for AF4-ICP-MS and SP-ICP-MS, respectively, with good and overall acceptable evaluation results obtained for all. The established and validated approach was demonstrated to be suitable for the characterization and quantitation of AgNPs in milk as well as the analysis of their migration from breast milk storage bags. [ABSTRACT FROM AUTHOR]

Our work aimed to examine nanoparticle levels in 69 distinct pooled mussel samples along the Norwegian coastline, considering samples from different environmental contexts, including natural locations, potentially polluted hotspots, and mussel farms. Single-particle ICP-MS was utilized to determine particle mass and number concentrations at environmentally relevant levels in addition to the total content of 11 elements: aluminum, barium, cerium, copper, iron, manganese, lead, silicon, silver, titanium, and zirconium. Results showed nanoparticle mass concentrations of few ng/g up to tens of μg/g and number concentrations of 10 6 to 10 9 particles/g (wet weight). Certain urban and industrially impacted locations were linked to increased levels of, e.g., silver, lead, cerium, zirconium, and titanium NPs. Farmed mussels exhibited lower concentrations. However, natural variations were considerable, and impacted locations mostly did not differ from the highest levels in pristine areas. The study presents the first extensive survey of NPs of 11 different elements in marine biota and provides evidence of increased levels of NPs in areas with anthropogenic activities.

Arsenic nanoparticles are alternative for arsenic compounds currently used in medicine. The preparation of suitable arsenic nanoparticles could significantly reduce the doses of arsenic administered and thus eliminate negative side effects. A method for controlled synthesis of arsenic nanoparticles is proposed and described. The preparation of arsenic nanoparticles, based on the simple reduction of sodium arsenite by sodium tetraborohydride in aqueous solution, led to the production of amorphous, spherical nanoparticles with diameters between 50 and 90 nm. Diameter was controlled simply by varying the pH value of the solution within the range of 5.5–11.0. The addition of cetyl trimethylammonium bromide into the reaction mixture allowed the preparation of small crystalline arsenic nanoparticles with an average diameter of approximately 4 nm, and the addition of bovine serum albumin led to bottle-like amorphous arsenic nanoparticles. The prepared nanoparticles were characterised using the single-particle inductively coupled plasma mass spectrometry method, ultraviolet–visible spectroscopy and electron microscopy. [ABSTRACT FROM AUTHOR]

Silver nanoparticles are widely used in cosmetics for their significant antiseptic and antimicrobial properties. This paper focuses on the development, optimisation and application of the cosmetics sample preparation procedure for silver nanoparticle determination and characterisation using single particle inductively coupled plasma mass spectrometry (sp-ICP-MS). The stability of silver nanoparticles in various extraction agents was studied along with the effect of the agents' concentration, extraction time and sample weight on extraction yield and observed nanoparticle diameter. A 0.1% (v/v) methanol solution was selected as the optimal extraction agent. The ratio of 5 mL methanol solution per 0.05 g of sample, with 25 min of sonication, was established as the optimal preparation procedure. Due to the elevated ionic background, the typical size detection limit was 33 nm. The concentration limit of quantification was 5280 mL–1 in the analysed dispersion, which corresponds to 528,000 particles per gram of the original sample. Finally, five commercially available cosmetics samples claiming to contain silver nanoparticles were analysed utilising the optimised procedure and sp-ICP-MS found silver nanoparticles with broad size distributions in three of the samples. Using transmission electron microscopy, silver nanoparticles below sp-ICP-MS size detection limit were also found in the remaining samples. The total Ag content in samples was determined and ranged from 0.45 to 20.0 µg.g–1, and the estimated contribution of AgNP to the total Ag content ranged from 0.02 to 1.9%. [ABSTRACT FROM AUTHOR]

Children are potentially exposed to products that contain nanoparticles (NPs). In particular, silver NPs are commonly present both in products used by and around children, primarily due to their antibacterial properties. However, very few data are available regarding the ability of silver NPs to penetrate through the oral mucosa in children. In the present work, we used baby porcine buccal mucosa mounted on vertical Franz diffusion cells, as an in vitro model to investigate penetration of silver NPs (19 ± 5 nm). Permeability experiments were performed using pristine physiologically-relevant saline solution in the receiver chamber and known concentrations of NPs or ions in the donor chamber; conditions mimicked the in vivo physiological pH conditions. After physicochemical characterization of silver nanoparticles dispersed in physiological solution, we evaluated the passage of ions and NPs through the mucosa, using single particle inductively coupled plasma mass spectrometry. A flux of 4.1 ± 1.7 ng cm−2 min−1 and a lag time of 159 ± 17 min were observed through mucosa exposed to silver nanoparticles. The latter suggests nanoparticle penetration through the baby porcine mucosa and release Ag+ ions in the receptor fluid, as confirmed by computational model. Due to physiological similarity between human and pig membranes it is reasonable to assume that a trans-oral mucosa penetration could occur in children upon contact with silver nanoparticles. [ABSTRACT FROM AUTHOR]

The accumulation of engineered nanomaterials (ENMs) will increase as more applications are discovered for their unique properties and characteristics. Additionally, the presence of nanomaterials in the environment becomes exacerbated as more consumer products containing nanoparticles are approved for use. Some examples of nano-enabled products include cosmetics, plastic packaging, clothing, textiles, and paints. Once exposed to natural environmental settings, a variety of transformations may occur leading to agglomeration, dissolution, or secondary particle formation. It is debated whether the toxic effects of nanoparticles stem from the particles themselves, ionic species, or formation of secondary particles. Therefore, understanding the behavior of nanoparticles in the environment, such as their permeability into biological tissues, becomes key to understanding the toxicological effects of nanoparticles. Many advancements have been made with ICP-MS to understand the behavior of nanoparticles in the environment and in biological systems, as well as analysis of nanomaterials in complex matrices. The development of single particle inductively coupled mass spectroscopy (SP-ICP-MS) has been imperative to understanding nanoparticle behavior in environmental and biological matrices. Additionally, the modification of the various sample introduction systems and mass analyzers has been constantly ongoing, which has further developed the applications and utility of SP-ICP-MS. [ABSTRACT FROM AUTHOR]

BACKGROUND The transformation of nanoparticles (NPs) internalized in plant tissues is the human digestive system that can provide a better understanding of the impact of NPs on the human system. The presented methodology was developed to study the bioaccessibility of cerium oxide (CeO2) and copper oxide (CuO) NPs from radish after the in vitro simulation of gastrointestinal digestion using single‐particle inductively coupled plasma mass spectrometry (SP‐ICP‐MS). RESULTS: Radish plants were cultivated hydroponically in a growth medium containing: (i) CeO2 NPs and (ii) CuO NPs. Both cerium (Ce) and copper (Cu) were found in all organs of the radish plants after analysis by standalone ICP‐MS. This confirms the bioaccumulation of CeO2 and CuO NPs and the translocation of their Ce and Cu to the aerial parts of the plant. Less Ce (4.095 μg g−1) has been detected in leaves than in roots (1.156 mg g−1) while Cu content in leaves was 5.245 μg g−1 and in roots was 10.41 μg g−1. Analysis of the digestive extracts obtained after the in vitro simulation of gastro (pepsin) and gastrointestinal (pancreatin) digestion showed that Ce has easy access to human system at least by 73%. CONCLUSION: The size of CeO2 NPs in digestive extracts showed no significant changes. However, the results obtained for CuO NPs digestion were variable and suggested that CuO NPs dissolved during the digestion process. The CuO NPs were observed in roots after the gastrointestinal digestion concluding that CuO NPs recovered after the initial dissolution. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Effluent from wastewater treatment plants contains a wide variety of engineered nanoparticles (ENPs) released from different sources. Although single type ENPs have been studied extensively with respect to their environmental impact, ENPs in mixed forms have not been investigated much at environmentally relevant concentrations. This study was designed to test the effect of mixed ENPs at three combinations and concentrations on an aquatic bacterial community. After mixing artificial treated wastewater with river water and exposing the microbial community to ENPs for three days, the ENPs were characterized by SP-ICP-MS. Results from this study showed that: 1) the size distribution of Ti and Zn at the beginning and end of the experiment did not vary much among all tested conditions. For Ag, the most frequent size increased more than 2-fold when the highest Ag ENPs were added; 2) particle concentrations of ENPs generally correlated positively with added concentrations; 3) dissolved Zn and Ag increased significantly as a result of spike; and 4) the bacterial community structure was shifted significantly as a consequence of ENPs' addition. With the dominant population being suppressed, the community exposed to ENPs became more diverse and even. Surprisingly, further increase of the doses of the three ENPs did not bring significant change to the microbial community. These results revealed that ENPs could bring significant impacts to prokaryotes even at low concentrations. But these impacts do not necessarily correlate positively with doses. Image 1 • The dominant phylum in the bacterial community was suppressed significantly. • The community structure was affected significantly by the spiked ENPs. • Particle concentrations of TiO 2 , ZnO and Ag correlated positively with added concentrations. • Dissolved metal ions contributed to the change of microbial structure. [ABSTRACT FROM AUTHOR]

This work demonstrates the effect of NaCl and carbon-related interferences on the analysis of arsenic and silver nanoparticles (NPs) by single-particle inductively coupled plasma mass spectrometry. Spectral interference caused by ArCl+ ions disturbing arsenic NPs analysis was eliminated using ammonia as reaction gas in a dynamic reaction cell of inductively coupled plasma mass spectrometer. In comparison to aqueous dispersions, non-spectral interferences caused by sodium lead to under-evaluation of arsenic and silver NPs diameter by about 7% and 15% at NaCl concentration of 450 mg L−1 and about 28% and 41% at NaCl concentration of 4500 mg L−1, respectively. As a consequence of lower transport efficiency, sodium non-spectral interferences also lead to about a 9% lower number of detected NPs for dispersions of both arsenic and silver NPs in 4500 mg L−1 NaCl. On the contrary, measurement of NPs in matrices containing methanol gives results where Ag and As NPs diameter is over-evaluated by about 3% and 15% at a methanol content of 1% (v/v) and about 6% and 20% at a methanol content of 2% (v/v), respectively, in comparison to aqueous dispersions. In addition, the organic carbon species behave as surfactants and increase the transport efficiency; this leads to an increase in the determined number concentration of NPs. In comparison to aqueous dispersions, this is over-evaluated by about 17% for Ag NPs and about 10% for As NPs at a methanol content of 5% (v/v). Image 1 • Non-spectral interferences of sodium leads to under-evaluation of As NPs and Ag NPs diameter in sp-ICP-MS method. • Carbon-related non-spectral interferences leads to over-evaluation of As NPs and Ag NPs diameter in sp-ICP-MS method. • Sample matrix components affecting surface tension of water cause changes in nebuliser transport efficiency. [ABSTRACT FROM AUTHOR]

A method based on single-particle inductively coupled plasma mass spectrometry (sp-ICPMS) using a dwell time 50 μs for acquisition has been developed for silver nanoparticles (Ag NPs) determination and characterization in bivalve molluscs. Ultrasound assisted enzymatic hydrolysis has been proposed for a fast isolation of Ag NPs from seafood using pancreatin and lipase as extracting enzymes. Optimum extraction conditions imply ultrasonication at 80% amplitude for 10 min, using 10 mL of enzymatic solution (2 g L−1/2 g L−1 pancreatin:lipase, pH 7.4). Repeatability of the over-all procedure was 8%, and the limit of detection (LOD) in Ag NPs concentration was 0.417 × 107 NPs g−1 (the LOD in size was 13.6–16.2 nm). The analytical recovery was 92 and 103% when using Ag NPs standards of 40 and 60 nm, respectively. Several bivalve molluscs (clams, cockles, mussels, razor clams, oysters and variegated scallops) were analysed for total silver content (ICP-MS after microwave assisted acid digestion), and for Ag NPs by the proposed method. Ag NPs concentrations were from 1.56 × 107 to 59.2 × 107 NPs g−1. Mean sizes were within the 26–35 nm range. • Ag nanoparticles (number of particles and size distribution) in bivalve molluscs • Ultrasound assisted enzymatic hydrolysis as sample pre-treatment for silver nanoparticle isolation • Single particle – inductively coupled plasma – mass spectrometry for silver nanoparticle assessment [ABSTRACT FROM AUTHOR]

Abstract A reliable sample pre-treatment based on enzymatic hydrolysis has been fully optimized and validated for TiO 2 NPs isolation and determination/characterization in surimi (crab sticks). Efficient extractions have been found when using a pancreatin/lipase mixture at pH 7.4 and 37 °C for 12 h under continuous stirring. The proposed sample pre-treatment procedure has been found not to change TiO 2 NPs size distribution, therefore guaranteeing TiO 2 NPs integrity. TiO 2 NPs determination (TiO 2 NPs concentration) and TiO 2 NPs characterization (size distribution) were assessed by single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) working with dwell times in the microsecond range (high frequency of data acquisition). Method validation was performed for TiO 2 NPs concentrations and TiO 2 NPs sizes. Good repeatability (25% and 8% for TiO 2 NPs concentration and TiO 2 NPs most frequent size), and sensitivity (limit of detection of 5.28 × 105 NPs g−1for TiO 2 NPs concentrations, and 31.3–37.1 nm for TiO 2 NPs size) were obtained. Accuracy, calculated through analytical recovery was adequate. Recoveries for TiO 2 NPs standards of 50 and 100 nm were 108 ± 5 and 105 ± 4%, respectively. The proposed methodology was applied to several surimi samples for assessing TiO 2 NPs concentrations and size distribution. Some surimi samples were found to contain TiO 2 NPs (concentrations from 1.40 × 107 to 1.19 × 109 NPs g−1). TiO 2 NPs size distributions were very different among the samples, and some of them showed wide size ranges (the most frequent size varied from 53.8 to 62.1 nm; whereas, the mean size values were within the 73.4–217.5 nm range). Graphical abstract fx1 Highlights • Reliable enzymatic hydrolysis for TiO 2 nanoparticles isolation from surimi. • sp-ICP-MS determination/characterization of TiO 2 nanoparticles. • Analytical performances for the over-all procedure. • Presence of TiO 2 nanoparticles in several commercial surimi foodstuffs. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The use of nanomaterials is increasing but the real risk associated with their use in humans has to be defined. In fact, nanomaterials tend to accumulate in organs over a long period of time and are slowly degraded or eliminated by the body. Exosomes are nanovesicles actively shuttle molecules, including chemical products and metals, through the body. Macrophages scavenge the body from both organic and inorganic substances, and they use to release high amounts of exosomes. We hypothesized that macrophages may have a role in eliminating nanomaterials through their exosomes. We treated human primary macrophages with 20 nm gold nanoparticles (AuNPs), analyzing the presence of AuNPs in both cells and the released exosomes by the implementation of different techniques, including SP-ICP-MS and NTA. We showed that macrophages endocytosed AuNPs and released them through exosomes. Our study on one hand provide the evidence for a new methodology in the early identification of the nanomaterials levels in exposed subjects. On the other hand we depict a way our body shuttle virtually intact nanoparticles through macrophage-released exosomes. [ABSTRACT FROM AUTHOR]

The use of zinc oxide nanoparticles (ZnO NPs) in cosmetic and pharmaceutical industry has been increased in recent years due to their good properties as solar radiation filters and antibacterial agent. According to the literature, the potential toxicity of these NPs could be size-dependent and the amount of solubilized metal. This work investigates new reliable and straightforward methodologies that enables the determination of ZnO NPs, discriminating them from ionic zinc in cosmetic samples. Two different techniques of analysis have been applied in this study: high-resolution continuum source graphite furnace atomic absorption spectrometry (HR–CS–GFAAS), and "single particle" inductively coupled plasma mass spectrometry (sp-ICP-MS). Triton X-100 has been used as a surfactant for the formation of homogeneous and stable slurries which allowed the determination of the concentration and sizes of ZnO NPs and Zn2+ in baby creams, eyeshadows, and lotions. A central composite design (CCD) was performed for the two techniques to optimize the concentration of Triton X-100 and sonication time. For validation purpose, the results of Zn2+ and ZnO NPs contents achieved by HR–CS–GFAAS were compared with the total Zn content obtained by acid digestion of the samples. A size comparison of the ZnO NPs was also carried out with the data obtained through the two methodologies and validated with transmission electron microscopy (TEM). In the case of TEM analysis, two different media were tried to study possible agglomerates and interactions between the particles and the matrix. [Display omitted] • New methodologies for ZnO NPs analysis in real samples. • Improvements in Zn2+ and ZnO NPs speciation in cosmetics and pharmaceutical samples. • Low preparation of sample (NPs contained in the samples are not modified). • The use of Triton X-100 for sample slurry preparation resulted in excellent results for size and Zn species contains. • At our knowledge, the two proposed methods are the first ones for ZnO NPs and Zn2+ analysis in creams and lotions. [ABSTRACT FROM AUTHOR]

A variety of food and drink samples (n = 21) were analyzed to evaluate the presence of (nano-) particles in their composition. After assessment of the sample pre-treatment step, a fast screening analysis was performed for drinks by Dynamic Light Scattering showing particles from 10 to 300 nm that could correspond to organic or metallic NPs. Metallic NPs were identified in foods by Single-Particle mode Inductively Coupled Plasma Mass Spectrometry and Asymmetrical Flow Field-Flow Fractionation coupled to Multiangle Laser Light Scattering and Inductively-Coupled Plasma Mass Spectrometry. The determination of Ti, Si and Ag concentration in the initial food suspensions, after filtration and centrifugal ultrafiltration enabled to estimate the ionic and nanoparticles content. Si-containing particles can be present in cappuccino powder as large aggregates and Si- and Al-containing particles in hot chocolate. Ti-containing NPs (80–200 nm) were found in chewing gum and Ag NPs in silver pearls (50–150 nm) used for decoration pastry. [ABSTRACT FROM AUTHOR]

With the increase in the application of nano-consumer products containing engineered nanoparticles (NPs), the unintended environmental exposure to NPs has been inevitable. Because of the bioaccumulation of NPs, concern about their potential cytotoxicity to aquatic organisms is also growing. Although measuring tools for analyzing particle size and/or concentration of NPs in intracellular uptake of tissues have been well developed, a simultaneous analysis of the two characteristics is difficult. The objective of this study was to use single particle-inductively coupled plasma-mass spectrometry (sp-ICP-MS) to measure the bioaccumulation and particle size changes of NPs exposed to zebrafish ( Danio rerio ) for 7 days. The uptake of NPs in the liver, intestine, and gill tissues was confirmed by electron microscopic (EM) analysis. However, the primary particle size of NPs in tissues could not be determined by the EM analysis. Therefore, sp-ICP-MS coupled with alkaline digestion was used for the easy extraction and immediate analysis of NPs from tissues. Zebrafish were exposed to four NPs (30 and 80 nm gold/silver NPs; AuNPs/AgNPs). Uptake amounts of AgNPs in the liver and intestine were significantly higher than those of AuNPs. Although larger NPs were finally accumulated in the liver and intestine tissues, most of the smaller NPs were filtered in the gills. The sp-ICP-MS method coupled with alkaline digestion enabled the accurate analysis of size, size distribution, and mass concentration of NPs in an aquatic organism. [ABSTRACT FROM AUTHOR]

Applicability of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) using dwell times equal to or shorter than 100 μs has been tested for assessing titanium dioxide nanoparticles (TiO 2 NPs) in bivalve mollusks. TiO 2 NPs isolation from fresh mollusk tissues was achieved by ultrasound assisted enzymatic hydrolysis procedure using a pancreatin/lipase mixture. Optimum extraction conditions imply ultrasonication (60% amplitude) for 10 min, and 7.5 mL of a solution containing 3.0 g L −1 of pancreatin and lipase (pH 7.4). The developed method was found to be repeatable (repeatability of 17% for the over-all procedure, TiO 2 NPs concentration of 5.33 × 10 7  ± 8.89 × 10 6 , n = 11), showing a limit of detection of 5.28 × 10 6 NPs g −1 , and a limit of detection in size of 24.4–30.4 nm, based on the 3σ criteria, and on the 3σ/5 σ criteria, respectively. The analytical recovery within the 90–99% range (use of TiO 2 NPs standards of 50 nm at 7 and 14 μg L −1 as Ti). Several bivalve mollusks (clams, cockles, mussels, razor clams, oysters and variegated scallops) were analyzed for total titanium (ICP-MS after microwave assisted acid digestion), and for TiO 2 NPs by the proposed method. TiO 2 NPs concentrations were within the 2.36 × 10 7 -1.25 × 10 8 NPs g −1 range, and the most frequent sizes were from 50 to 70 nm. [ABSTRACT FROM AUTHOR]

In this work, arsenic species in mainstream cigarette smoke condensates was systemically studied with inductively coupled plasma mass spectrometry. A single particle inductively coupled plasma mass spectrometry was utilized for analysis of the physical forms of arsenic, and no particle arsenic was observed in mainstream cigarette smoke condensates. The solvent extraction experiments proved that the water-soluble arsenic was the main species in mainstream cigarette smoke condensates, which was consistent with the result of single particle inductively coupled plasma mass spectrometry. Furthermore, speciation of arsenite, arsenate, monomethylarsonic acid, and dimethylarsinic acid was investigated using high performance weak anion exchange chromatography coupled with inductively coupled plasma mass spectrometry detection. The developed high performance liquid chromatography coupled inductively coupled plasma mass spectrometry method was successfully applied to the determination of arsenic species in mainstream cigarette smoke condensates with satisfactory recoveries. Four arsenic species were detected in the mainstream cigarette smoke condensates from four brands of commercial available cigarettes, and there was a great difference between the arsenic content and composition among the different brands of cigarettes. It is found that arsenate was the main species in all tested cigarette samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • ElFFF provides information on hydrodynamic diameter of nanoparticles. • SP-ICP-MS provides information on core diameter of nanoparticles. • ElFFF with SP-ICP-MS provides information on electrophoretic mobility of nanoparticles. • ElFFF with SP-ICP-MS provides information on stabilizer layer thickness on nanoparticle surface. Electrical field-flow fractionation (ElFFF) is a sub-technique of field-flow fractionation utilized for separation of charged nanoparticles. ElFFF was applied for characterization of size and charge of nanoparticles by investigating the nanoparticle retention time. However, one of the parameters; i.e., size or charge of nanoparticles, must be known before characterizing another parameter. This work illustrates an application of normal ElFFF for nanoparticle characterization associated with single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) which was used for size determination. Six nanoparticles samples including 30 nm AuNPs stabilized by citrate, 60 nm AuNPs stabilized by citrate, mixture of 30 nm and 60 nm AuNPs stabilized by citrate, 60 nm silver nanoparticles (AgNPs) stabilized by polyethylene glycol (PEG), 100 nm AgNPs stabilized by citrate, and mixture of 60 nm AgNPs stabilized by PEG and 100 nm AgNPs stabilized by citrate were used as samples. The nanoparticles were prior separated in ElFFF system under 1.50 V applied voltage in deionized (DI) water carrier, then their fractions were collected for size determination using SP-ICP-MS. The charge, electrophoretic mobility, of nanoparticles was characterized by using the size determined from SP-ICP-MS and the retention time of nanoparticles via the ElFFF theoretical equation. The size and charge of nanoparticles characterized using ElFFF and SP-ICP-MS were in agreement with their size and charge reported in certificate. In addition, the size information obtained from ElFFF and SP-ICP-MS was applied for characterization of the layer thickness of stabilizing agent coated on nanoparticle surface of 60 nm AgNPs stabilized by PEG. With high sensitivity of inductively coupled plasma mass spectrometry (ICP-MS), this method shows potential use for characterization of nanoparticles in environmental system. [ABSTRACT FROM AUTHOR]

In recent years, silver nanoparticles (AgNPs) have attracted significant attention in medicinal, biomedical, and pharmaceutical research owing to their valuable physicochemical and antibacterial properties. Leaf sap extract (LSE) from Aloe arborescens can be used as an active ingredient for different biological applications, including wound healing. In this study, we have investigated the use of LSE from A . arborescens as a reducing, stabilizing and capping agent to produce AgNPs during the so called “green synthesis” (G-AgNPs). The objective of this study was to prepare, characterize and evaluate the potential of G-AgNPs against human pathogenic bacteria for the intended use as treatment of infected wounds. When the mixture of silver nitrate solution and LSE was exposed to direct sunlight it yielded a rapid color change from colorless to reddish-brown, indicating the formation of G-AgNPs. Physicochemical characterization such as Single particle inductively coupled plasma mass spectrometry, High resolution transmission electron microscopy and surface chemistry studies (Fourier transform infrared spectroscopy and X-Ray diffraction) revealed a small size in the range of 38 ± 2 nm, smooth surface and existence of LSE on the G-AgNPs. G-AgNPs possessed good antibacterial activity against both Pseudomonas aeruginosa and Staphylococcus aureus . The flow cytometry study revealed the increased percentage of dead cells treated by G-AgNPs through cell membrane damage, and it was further confirmed by confocal laser scanning microscopy. Thus, the present study reveals that the novel G-AgNPs demonstrated effective antibacterial properties against both Gram-negative and Gram-positive bacterial strains and shows great potential for its use in the treatment of pathogen infected wounds. [ABSTRACT FROM AUTHOR]

Cosmetics are part of the daily life of most of the people. Thus, a complete characterization of the products we applied in our skin is necessary. In this work, an analytical investigation of a wide variety of cosmetics from the point of view of total element content and metallic nanoparticles (NPs) has been performed. Firstly, we analyzed the total element content by ICP-MS and ICP-OES after acid digestion as an assessment of the presence of metal impurities. Prohibited elements in cosmetics, according to the European Commission regulation No 1223/2009, were not detected, and only elements mentioned in the label were found (e.g. Al, Fe, Ti and Si). Secondly, a screening of the presence of NPs has been performed by Dynamic Light Scattering (DLS) and Single Particle Inductively-Coupled Plasma Mass Spectrometry (SP-ICP-MS). Two sample preparation procedures were applied. The first protocol consisted in the preparation of suspensions in 0.1% w/v SDS and the second based on defatting with hexane followed by resuspension in water. DLS was employed as a routine method for a fast analysis of NPs, but this technique showed limitations due to the lack of specificity. SP-ICP-MS analyses were then performed, first as a screening technique to evaluate the presence of TiO 2 and Au NPs in cosmetics suspensions prepared in SDS; and second, when a positive answer was obtained about the presence of NPs from the screening, SP-ICP-MS was used for particle size determination. Results showed that only TiO 2 NPs were present in two sunscreens, one anti-wrinkle day cream, one lip balm protector labeled as ‘nano’ and in one brand of toothpaste not labeled as ‘nano’. Sizes obtained for both sample preparations were compared and ranged from 30 to 120 nm in most of the samples. [ABSTRACT FROM AUTHOR]

The lack of silver speciation exposure data in toxicity studies investigating the effects of manufactured silver nanoparticles (AgNPs) in natural soil media limits the ability to discern nano-specific effects from effects of the toxic Ag+ form, which may be released from the manufactured AgNPs contained in wastewater, biosolids or soil environment. Using samples containing Ag+ or mixtures of Ag+ and AgNPs, ranging in total Ag concentrations of 10-5 to 10-9 M, and prepared in de-ionised water and filtered soil extracts, the validity of the ion exchange technique (IET) to quantify Ag+ was investigated by comparing measurements to those of an Ag+ ion selective electrode (ISE) and to the dissolved fraction from single particle inductively coupled plasma-mass spectrometry (SP-ICP-MS) analysis (SP-dissolved). When analysing samples in the filtered soil extract, IET and ISE gave comparable results down to 10-7 M, below which Ag+ activities were below the ISE detection limit. For water samples, SP-dissolved values were generally comparable or slightly greater (on average 65%) compared with IET-Ag+ at all concentrations. The high bias was likely due to inclusion of unresolved particles below the SP-ICP detection limit of 19 nm. However, when analysing samples in the soil extract, SP-dissolved values were on average eight-fold greater than IET-Ag+, highlighting the effect that natural colloidal and dissolved soil constituents have on complexing Ag+, as well as the lack of specificity of the SP-dissolved analysis for the Ag+ species. IET is shown here to be a valid procedure to quantify Ag+ activity in soil extracts, and while the study highlights the limitations of using the SP-dissolved fraction to estimate this biologically relevant Ag fraction, it shows that combined, IET and SP-ICP-MS provide a valuable approach for investigating the behaviour of manufactured AgNPs in different matrixes. Environmental context: Environmental context: Biosolid-amended soils are likely sinks for manufactured silver nanoparticles, the environmental toxicity of which is believed to be related to the release and accumulation of Ag+ ions. This study demonstrates how an ion exchange technique can be applied to soil extracts to provide Ag+ measurements at low, environmentally relevant levels. The technique is a valuable addition to existing analytical methods for tracking the behaviour of Ag nanoparticles and Ag+ ions in the terrestrial environment. [ABSTRACT FROM AUTHOR]

• Optimized centrifugation approach was successfully developed to separate NPs from sediments. • Ti-based NPs had the highest concentrations in both seawaters and sediments for the five types of NPs. • The highest abundance of metal-based NPs in seawaters was observed around the Yellow River Estuary. • One sampling site was assessed as "high risk" to marine ecosystems for both Ag- and Ti-based NPs. Metal-based nanoparticles (NPs) attract increasing concerns because of their adverse effects on aquatic ecosystems. However, their environmental concentrations and size distributions are largely unknown, especially in marine environments. In this work, environmental concentrations and risks of metal-based NPs were examined in Laizhou Bay (China) using single-particle inductively coupled plasma-mass spectrometry (sp-ICP-MS). First, separation and detection approaches of metal-based NPs were optimized for seawater and sediment samples with high recoveries of 96.7% and 76.3%, respectively. Spatial distribution results showed that Ti-based NPs had the highest average concentrations for all the 24 stations (seawater, 1.78 × 108 particles/L; sediments, 7.75 × 1012 particles/kg), followed by Zn-, Ag-, Cu-, and Au-based NPs. For all the NPs in seawater, the highest abundance occurred around the Yellow River Estuary, resulting from a huge input from Yellow River. In addition, the sizes of metal-based NPs were generally smaller in sediments than those in seawater (22, 20, 17, and 16 of 22 stations for Ag-, Cu-, Ti-, and Zn-based NPs, respectively). Based on the toxicological data of engineered NPs, predicted no-effect concentrations (PNECs) to marine species were calculated as Ag at 72.8 ng/L < ZnO at 2.66 µg/L < CuO at 7.83 µg/L < TiO 2 at 72.0 µg/L, and the actual PNECs of the detected metal-based NPs may be higher due to the possible presence of natural NPs. Station 2 (around the Yellow River Estuary) was assessed as "high risk" for Ag- and Ti-based NPs with risk characterization ratio (RCR) values of 1.73 and 1.66, respectively. In addition, RCR total values for all the four metal-based NPs were calculated to fully assess the co-exposure environmental risk, with 1, 20, and 1 of 22 stations as "high risk", "medium risk", and "low risk", respectively. This study helps to better understand the risks of metal-based NPs in marine environments. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite the continual improvement of quality of life with nanotechnological applications, nanoparticles (NPs) will inevitably reach our living environment and various ecosystems. Plants act as a crucial interface between humans and their environment. The wide use of NPs has raised great concerns about the risk of potential toxicity in crop health and food safety, leading to an emerging research theme about the interaction between plants and NPs. However, even the basic issue concerning the eventual fate and characteristics of NPs after internalization is not clearly delineated due to lack of a well-established technique for NP analysis in plant tissues. With the aid of enzymatic digestion, single particle-inductively coupled plasma-mass spectrometry (SP-ICP-MS) is employed to determine the size distribution of silver nanoparticles (Ag NPs) in tissues of the model plant Arabidopsis thaliana after exposure to 10 nm Ag NPs. Our results show that Macerozyme R-10 is an appropriate enzyme to release Ag NPs from Arabidopsis plants without changing the properties of nanomaterials. The characteristics of Ag NPs obtained by SP-ICP-MS in both roots and shoots are in agreement with our transmission electron micrographs, demonstrating that SP-ICP-MS coupled with enzymatic digestion procedure is a powerful technique for quantitative determination of NPs in plant tissues. Our data reveal that Ag NPs tend to accumulate predominantly at root tissues whereby a minor portion is transported to shoot tissues. Furthermore, the measured size distribution of Ag NPs in plant tissue is centred at around 20.70 nm, larger than the average 12.84 nm in diameter, strongly implying that many internalized Ag NPs do not exist as intact individual particles but are aggregated and/or biotransformed by plant cells.

Single particle-inductively coupled plasma-mass spectrometry (SP-ICP-MS) has become a powerful technique for the characterization of nanoparticles (NPs). However, the accuracy of the characterization of NPs by SP-ICP-MS is greatly affected by the data acquisition rate and the way of data processing. For SP-ICP-MS analysis, ICP-MS instruments typically apply microsecond to millisecond dwell times (10 μs–10 ms). Considering the duration of one nanoparticle event in the detector is 0.4–0.9 ms, NPs will show different data forms when working with microsecond and millisecond dwell times. In this work, the effects of dwell times from microsecond to millisecond (50 μs, 100 μs, 1 ms and 5 ms) on the data forms in SP-ICP-MS analysis are discussed. The data analysis and data processing for different dwell times is discussed in detail, including the measurement of transport efficiency (TE), the distinction of signal and background, the evaluation of diameter limit of detection (LOD d) and the quantification of mass, size and particle number concentration (PNC) of NPs. This work provides data support for the data processing process and aspects to be considered in the characterization of NPs by SP-ICP-MS, which is expected to provide guidance and reference for researchers in SP-ICP-MS analysis. [Display omitted] • The effect of dwell times on data acquisition quality is investigated in SP-ICP-MS analysis. • The differences in data processing between millisecond and microsecond dwell times are compared and discussed in detail. • Particle size method using standard NPs and standard solutions can be used to evaluate transport efficiency accurately. • A methodology set for the characterization of nanoparticles using SP-ICP-MS is provided. [ABSTRACT FROM AUTHOR]

This work studies the presence of the Ti, Al and V metal ions and Ti nanoparticles released from the debris produced by the implantoplasty, a surgical procedure used in the clinic, in rat organs. The sample preparation for total Ti determination was carefully optimized using microsampling inserts to minimize the dilution during the acid attack of the lyophilized tissues by a microwave-assisted acid digestion method. An enzymatic digestion method was optimized and applied to the different tissue samples in order to extract the titanium nanoparticles for the single-particle ICP-MS analysis. A statistically significant increase was found for Ti concentrations from control to experimental groups for several of the studied tissues, being and particularly significant in the case of brain and spleen. Al and V concentrations were detected in all tissues but they were not different when comparing control and experimental animals, except for V in brain. The possible presence of Ti-containing nanoparticles mobilized from the implantoplasty debris was tested using enzymatic digestions and SP-ICP-MS. The presence of Ti-containing nanoparticles was observed in all the analyzed tissues, however, differences on the Ti mass per particle were found between the blanks and the digested tissue and between control and experimental animals in some organs. The developed methodologies, both for ionic and nanoparticulated metal contents in rat organs, have shown the possible increase in the levels of Ti both as ions and nanoparticles in rats subjected to implantoplasty. [Display omitted] • A method for the analysis of the individual titanium nanoparticles in biological tissues by SP-ICP-MS has been proposed. • A methodology for the quantification of Ti, Al and V in tissues at trace levels has been optimized. • Implantoplasty-derived metallic debris can cause an increase in Ti species in organs, including ions and nanoparticles. [ABSTRACT FROM AUTHOR]

It is challenging to separate and measure the physical and chemical properties of monometallic and bimetallic engineered nanoparticles (NPs), especially when mixtures are similar in size and at low concentration. We report that single particle inductively coupled mass spectroscopy (SP-ICP-MS), alongside field flow fractionation (FFF), has allowed for the accurate measurement of size and particle number concentrations of mixed metallic nanoparticles (NPs) containing monometallic NPs of gold (Au) and silver (Ag) and a bimetallic core-shell structured NP (Au@Ag) of equivalent size. Two sets of these NPs were measured. The first contained only 60 nm particles, where the Au@Ag NP had a 30 nm core and 15 nm shell to make a total diameter of 60 nm. The second contained only 80 nm particles (Au@Ag NP core particle of 50 nm with a 15 nm shell). FFF separation was used here as a sizing technique rather than a separation technique. It was used to confirm that suspensions containing either individual or mixtures of the Au 60 nm, Ag 60 nm and AuAg 60 nm suspensions eluted together and were of the same size. Similarly, FFF was used to show that suspensions containing individual or mixtures of the equivalent 80 nm, eluted together and were of the same size. Although the 60 nm and 80 nm suspensions did not elute at the same time they were not run together. SP-ICP-MS is then used to identify the size and concentration of the particles within the suspension. Successful separation of the NPs was effected and the limits of the instrument were obtained. [ABSTRACT FROM AUTHOR]